Fox Broadcasting is overhauling much of its prime-time lineup after a disappointing season.

The network, which endured steep declines in overall viewers and in the coveted 18-to-49-year-old demographic, said it will premiere 12 new shows next season. Only two of the shows it launched this season -- the comedy "Brooklyn Nine-Nine" and the drama "Sleepy Hollow" -- made it to next fall.

"This past one was a tough one for us," said Fox Entertainment Chairman Kevin Reilly. According to Nielsen, not including sports, Fox's prime-time lineup averaged about 5.9 million viewers. viewers. Last season Fox averaged 6.7 million viewers.

New shows weren't Fox's only problem this season. The juggernaut "American Idol" came crashing to Earth. Last week, one of the episodes of "American Idol" averaged just 7 million viewers. The median age for the show is now over 50. When it made its debut more than a decade ago, the typical "Idol" viewer was about 30.

Fox's "Dads," which came under fire for what critics and others saw as offensive humor, has been canceled, along with two other freshman comedies, "Enlisted" and "Surviving Jack."

"Dads" in particular has been a lightning rod for Fox, even before its premiere in September. The comedy starred Seth...

(Greg Braxton)

The number of hours allotted for "American Idol" will be scaled back dramatically next season, to 37 from more than 50 this season. Reilly said he is optimistic that Jennifer Lopez, Harry Connick Jr. and Keith Urban will return as judges.

But the days of "American Idol" dominating the ratings are over, Reilly said.

"'Idol' is not going to come back as the ratings champion it once was," Reilly said. But the network isn't ready to throw in the towel. Reilly said it can be a "potent" show "for many years to come."

The network's new programs include "Gotham," a prequel of sorts to "Batman" starring Benjamin McKenzie ("Southland") as a young Commissioner Gordon rising up through the ranks by putting down the bad guys. The noirish "Gotham" also stars Donal Logue and Jada Pinkett Smith. It will air at 8 p.m. Mondays as a lead-in to "Sleepy Hollow."

A behind-the-scenes look at filming around the world for television and movies as seen from the streets.

"This is sure to be this season’s biggest and noisiest hit," Reilly predicted.

Fox's other big fall drama bet is "Red Band Society," a quirky drama about high school kids living in a pediatric ward of a hospital. Oscar winner Octavia Spencer plays a nurse in charge of the ward and the executive producers include Steven Spielberg and Justin Falvey, whose credits include FX's critically acclaimed "The Americans." "Red Band Society" is scheduled for Wednesdays at 9 p.m., following the reality show "Hell's Kitchen.

Fox will also try its luck with "Gracepoint, a remake of the British hit "Broadchurch" about the murder of a child and the effect it has on a small California town. Called an event series by the network, "Gracepoint" will run for 10 weeks in the fall at 9 p.m. on Thursdays, following the veteran crime drama "Bones." It stars Anna Gunn of "Breaking Bad" fame and Nick Nolte.

The network's other big move is relocating "Brooklyn Nine-Nine," a low-rated critical darling, from Tuesday at 8:30 p.m. to Sunday at 8:30 p.m. where it will have a strong lead-in from "The Simpsons." Fox is also debuting the new comedy "Mulaney" at 9:30 p.m. Executive produced by "Saturday Night Live" creator Lorne Michaels, "Mulaney" stars John Mulaney as a comedian who ends up writing for an obnoxious game show host played by Martin Short.

For Fox, this marks the first time in several years it is attempting live-action comedies on Sunday night, which previously has been all animation.

On the reality front, Fox will try its own version of the long-running CBS hit "Survivor." Called "Utopia," it will strand 15 people in an undeveloped part of the world for a year and film them trying to create their own society. "Utopia" will air on Tuesdays at 8 p.m. and Fridays at 9 p.m.

Reilly said "Utopia" is a "very big bet" and the most compelling unscripted show in "quite some time."

Fox also announced several shows for the spring, including the drama "Empire" and the comedy "The Last Man on Earth."

"Empire" stars Terrence Howard as the head of a powerful music label whose biggest threat may be his own family. Lee Daniels, the director of "The Butler" and "Precious," created the series. "The Last Man on Earth" is a dark comedy starring Will Forte as literally the last man on the planet who roams the country in an RV looking for others.